Senechal, who was retired, had been a member of the Asheville-based birding group for years.

"She was a wonderful photographer and was very interested in nature," Tribble said. "She was very generous with her knowledge and expertise. It's just incredibly sad. We're all in shock. She's going to be really missed."

According to arrest warrants, Alexander was traveling "in excess of posted speed approaching a sharp curve, losing control of the vehicle. This violation was the proximate cause of death."

He was driving "carelessly and heedlessly in willful and wanton disregard for the rights and safety of others," warrants stated.

The speed limit on Kimberly Avenue at the site of the accident is 20 mph. Police have not released an estimate of Alexander's speed when the accident happened.

Investigators consulted with the Buncombe District Attorney's office before filing the charges, Romick said.

"It's an absolute tragedy," said Simon Thompson, another friend from the Audubon Society. "You don't expect to be hit on a sidewalk, where you're supposed to be. How can you lose control on a road like that? I'm just amazed."

Alexander also was served with an outstanding warrant for failing to appear on a 2011 misdemeanor charge of operating a vehicle with no insurance.

He was released under a $2,000 unsecured bond.

Alexander's court date on the death by vehicle and reckless driving charges is scheduled for Aug. 7 in Buncombe County District Court.